Glenn Greenwald (right) and his partner David Miranda after testifying before lawmakers. Photo: Reuters

Brazil-based US reporter Glenn Greenwald says he will publish documents from intelligence leaker Edward Snowden focused on France and Spain.

Greenwald, a Rio de Janeiro-based correspondent for Britain's Guardian newspaper, also said that if Brazil wanted more data on alleged US snooping into its affairs it should offer Snowden asylum.

Brazil did not respond to a Snowden asylum request as he sought refuge after his first explosive disclosures detailing the US government's digital dragnet.

Testifying before a Brazilian congressional panel, Greenwald accused Washington and its allies of waging a "war against journalism and the process of transparency".

"I am learning now that the United States is using this surveillance system to punish the journalistic process," said Greenwald, who, without elaborating, added he was working on material relating to France and Spain.

"We are undertaking high-risk journalism. We shall continue doing so until we publish the last document I have," Greenwald told senators investigating allegations that Washington spied on Brasilia.

When he testified before the Brazilian Senate's foreign relations committee in August, Greenwald said he had received thousands of documents from Snowden while in Hong Kong with the fugitive.

On Wednesday, as Brazil announced it would host an internet governance summit next year, Greenwald said: "Every time I found a document I thought ought to be published, I immediately started working on it as quickly as possible to inform the public."

The disclosures led Brazilian President Dilma Rousseff to slam the United States in an address to the United Nations last month.

This article appeared in the South China Morning Post print edition as French secrets next, says Greenwald

I'm glad things are coming out, can't believe this has all been going on since 1996 when Annie Machon came out. She never got as much exposure as Snowden and the more recent leakers maybe if we paid more attention to what she had said things wouldn't be as bad ****www.youtube.com/watch?v=XfcDT8vsaJA